Atmospheric pressure CVD process for preparing fluorine-doped tungsten oxide films

Abstract

A film of fluorine-doped tungsten oxide is provided on a substrate by reacting together tungsten alkoxide, an oxygen-containing compound, and a fluorine-containing compound.

We claim: 
     
       1. A process for providing fluorine-doped tungsten oxide on the surface of a substrate, which process comprises reacting together a tungsten alkoxide, an oxygen-containing compound, and a fluorine-containing compound at the surface of the substrate at a temperature and for a time sufficient to form a film of fluorine-doped tungsten oxide on the substrate. 
     
     
       2. The process according to claim 1, wherein the tungsten alkoxide is selected from the group consisting of tungsten V ethoxide and tungsten VI ethoxide. 
     
     
       3. The process according to claim 1, wherein the oxygen-containing compound is oxygen gas. 
     
     
       4. The process according to claim 3, wherein the oxygen gas is mixed with another oxygen-containing compound selected from the group consisting of isopropyl alcohol, ethyl alcohol and t-butyl alcohol. 
     
     
       5. The process according to claim 1, wherein the fluorine-containing compound is 1,1-difluoroethane. 
     
     
       6. The process according to claim 1, wherein the temperature is from about 300° C. to about 500° C. 
     
     
       7. The process according to claim 1, wherein the molar ratio of tungsten alkoxide to oxygen-containing compound is from about 2:1 to about 1:5. 
     
     
       8. The process according to claim 1, wherein the fluorine-containing compound comprises from about 1% to about 50% by weight of the reaction mixture. 
     
     
       9. The process according to claim 1, wherein the tungsten alkoxide is selected from the group consisting of tungsten V ethoxide and tungsten VI ethoxide; the oxygen-containing compound is selected from the group consisting of oxygen, isopropyl alcohol, ethyl alcohol, and t-butyl alcohol, and mixtures thereof; and the fluorine-containing compound is 1,1-difluoroethane, the molar ratio of tungsten alkoxide to oxygen-containing compound being from about 2:1 to about 1:3 the 1,1-difluoroethane being from about 5% to about 30% by weight of the reaction mixture, and the temperature is from about 300° C. to about 500° C. 
     
     
       10. The process according to claim 1, wherein the substrate is glass. 
     
     
       11. A process for coating glass, comprising the steps of: A) providing a glass substrate, having a surface; and   B) reacting at the surface of the substrate tungsten alkoxide, an oxygen-containing compound, and a fluorine-containing compound, at a temperature and for a time sufficient to form a layer of fluorine-doped tungsten oxide on the surface of the glass substrate.   
     
     
       12. A process according to claim 11, wherein said tungsten alkoxide is selected from tungsten V ethoxide and tungsten VI ethoxide. 
     
     
       13. A process for coating glass according to claim 11, wherein the oxygen-containing compound is selected from the group consisting of oxygen, isopropyl alcohol and t-butyl alcohol, and mixtures thereof. 
     
     
       14. The process for coating glass according to claim 11, wherein the fluorine-containing compound is 1,1-difluoroethane. 
     
     
       15. The process for coating glass according to claim 11, wherein the temperature is from about 300° C. to about 500° C. 
     
     
       16. The process for coating glass according to claim 11, wherein the molar ratio of tungsten alkoxide to oxygen-containing compound is from about 2:1 to about 1:5. 
     
     
       17. The process for coating glass according to claim 11, wherein the fluorine-containing compound comprises from about 1% to about 50% by weight of the reaction mixture. 
     
     
       18. A process for preparing a blue tinted, electrically conductive, infrared radiation reflecting coated glazing for automotive or architectural use, comprising the steps of: A) providing a glass substrate, having a surface; and   B) reacting at the surface of the substrate tungsten alkoxide selected from the group consisting of tungsten V ethoxide or tungsten VI ethoxide; an oxygen-containing compound selected from the group consisting of oxygen, isopropyl alcohol, ethyl alcohol, and t-butyl alcohol, and mixtures thereof; and 1,1-difluoroethane; the molar ratio of tungsten alkoxide to oxygen-containing compound being from about 1:1 to about 1:3, the 1,1-difluoroethane being from about 5% to about 30% by weight of the reaction mixture, at a temperature from about 300° C. to about 500° C. and for a time sufficient to form a layer of fluorine-doped tungsten oxide on the surface of the glass substrate.   
     
     
       19. A process for incorporating fluorine atoms into tungsten oxide, as the tungsten oxide is being formed by a reaction between tungsten alkoxide and an oxygen-containing compound, comprising reacting with the tungsten alkoxide and the oxygen-containing compound a fluorine-containing compound selected from the group consisting of 1,1-difluoroethane, 1,1,1-chlorodifluoroethane, 1,1-difluoroethylene, chlorotrifluoroethylene, carbonyl fluoride, sulfur hexafluoride, nitrogen trifluoride, trifluoroacetic acid, bromotrifluoromethane, trifluoroacetic anhydride, ethyl trifluoroacetoacetate, trifluoroethanol, ethyl trifluoroacetate, pentafluoropropionic acid, heptafluorobutyryle chloride, 1,1,1-trifluoroacetylacetone, Freon, 2-chloro-1,1,2-trifluoroethylmethyl ether, chlorodifluoroacetic acid, difluoroacetic acid, ethyl chlorofluoroacetate, methyl trifluoroacetate, ethyl-4,4,4-trifluoroacetoacetate, hydrofluoric acid, as well as mixtures and derivatives thereof, to form fluorine-doped tungsten oxide.